Speed-regulating apparatus.



J. B. TAYLOR.

SPEED REGULATING APPARATUS.

APPLICATION HLED DEC-1. 1914.

1,227,091 A Patented May 22, 191%.

WITNESSES I l/VI/E/VTOB Jzahn BTaglor BY M M M TTURNEYS JOHN B. TAYLOR,015' SGHENECTADY, NEW YORK.

SPEED-REGULATING APPARATUS.

Specification of Letters Patent.

Patented May 22, 1917.

Application filed December 1, 1914. Serial No. 875,010.

To all whom it may concern.

,Be t known that 1, JOHN B. TAYLon,.a citize'n of the United States,residing in Schenectady, county'of Schenectady, State of New York, haveinvented certain new and useful Improvements in Speed-RegulatingApparatus; and I do hereby declare the following to be a full, clear,and exact description of the invention, suchas will enable othersskilled in the art to which it appertains to make and use the same.

' stretched so that they may vibrate much like the strings of a piano.Preferably these strings are mounted in the musical instrument so as tobe subject to temperature and other atmospheric changes in the same wayand to the same extent as the sounding strings of the instrument. Thesevibrating strings of the speed. regulator are tuned, one slightly abovea certain pitch and the other slightly below that pitch. Then, byproviding current connections whereby the strings may be mechanicallyvibrated with a speed corresponding to the speed of the motor to becontrolled, any change infrequency of that motor will cause one of thestrings to vibrate with greater amplitude than the other. By mounting asuitable stop or movable element controlled in position bythedifferential action of the two strings, connections may be made or otherchanges effected whereby the. motor is either increased or decreased inspeed and returned to its normal or standard rate of rotation. The

mechanical details may be varied in many Ways, and the electricalmechanism for vibratingthe strings and for using their differences inamplitude of vibration may be constructed in many ways, but for thepurpose of making clear'the central idea of my present invention, I havedisclosed in the accompanying drawings, somewhat diagrammatically, oneembodiment thereof.

In the accompanying drawings, Figure 1 is a perspective illustration,largely diagrammatic, showingthe vibrating strings and the magnet bywhich they are vibrated, and the differential mechanism by which thatdifference in vibration is utilized.

F 2 is a diagram of the electrical connections.

Fig. 3 illustrates a modification of the invention.

In the embodiment illustrated, the vibra+- ing strings 1 and 2 are shownas mounted on a suitable support over bridges 3 and at and tuned bymeans of pegs 5 and'6 until the natural vibratory period of string 1 issomewhat higher than a certain standard, and the natural vibratoryperiod of string 2 is lower than that standard by an equal amount. 7 v

A means is provided for vibrating the strings either continuouslyoraoccasionally,

' as the circumstances may require, this means comprising a U-shapedelectroinagnet 7 energized by pulsating current transmitted from thecurrent supply conductors 8 and 9 through a suitable interrupter 10,driven in synchronism with the motor 11 of the musical instrument orother device. If desired a commutator may be directly coupled with themotor, as indicated in Fig. 2. Alternating current may be used in placeof pulsating current when more conveniently obtainable, as by the use ofan alternating current generator in place of interrupter 10, but whetheralternating current or pulsating current is used, the vibratory efi'ectsetup in the tightly stretched Wires 1 and 2 should represent the speedof motor 11, and for normal speed of that motor, should be intermediatebetween the normal vibratory periods of the wires 1 and 2. In Fig. 3there is shown an alternating current generator 25 driven by the motor11 and adapted to energize the magnet 7 over conductors 26. When thespeed'of the motor increases, the pulsations at the electromagnet willmore closely approach the natural vibratory period of string 1, and theamplitude of its vibration will be increased thereby, while at the sametime the vibrations of string 2 will decrease,- and, similarly, on adecreasing speed of the motor, the pulsations of the electromagnet willmore closely approach the normal vibration of string 2 and the amplitudeof the latter will increase.

Differential mechanism of various types may be utilized for convertingthis variation in the mechanical vibration of strings 1 and 2 intomechanical movement whereby the motor maybe restored to normal speedcorresponding to vibrations intermediate between the two strings, andthe device now preferred by me comprises a stop 12 pivoted at 13, thisstop having a head 14 faced with a layer of felt and in position toreceive blows from the vibrating strings, and having a tail 15 forvarying the effectiveness of the resistance in the motor field circuit.

The motor here illustrated has a shunt field 16 with a resistance 17 inseries there with across the armature. The outer end of resistance 17 isconnected to an adjustable contact 18, and the outer end of the fieldwinding 16 is connected to a similar adjustable contact 19 through aresistance 20. Be-

tween the contacts 1'8 and 19, and in position to establish connectiontherewith, is the tail 15' of the swinging element 12, which moves onits pivots 13 in accordance with the differential action of thevibrating strings 1 and 2. The inner end of field winding 16 isconnected to the pivots 13 and so completes the connection to theswinging tail 15. This arrangement of resistances, field winding andvibrating contact is somewhat in the nature of a T irrill regulator,effective for varying the excitation of the motor by controlling theshunt around the field winding, for as the speed of the motor increasesabove normal, the amplitude of the high pitched wire- 1 will increaseand the amplitude of the low pitched wire 2 will decrease, and theirdifferential action will cause the swinging element 12 to vibrate intoand out of engagement with contact 18, thereby re- .ducing the effectiveresistance in circuit with the field 16 and thus strengthening-the fieldand bringing the motor speed down toward normal. If, on the other hand,the. motor speed tends to drop off, as because of a sudden heavy load onthe motor, the swinging tail 15 will vibrate into and out of connectionwith contact 19, thus shunting current through resistance 20 and aroundthe field 16, thereby decreasing the field excitation and causing themotor to increase in speed. At normal speed for the motor the swingingelement 12 will be in its mid-position with its tail 15 vibratingbetween contacts 18 and 19.

I am aware that other means may be provided for utilizing thedifferential action of the two strings or wires to accelerate or retardthe motor, and that it is not necessary to operate on the motor fieldcircuit and that the motor and its adjuncts may be of a character quitedifferent from those indicated diagrammatically by the drawings, andthat other governing and controllin mechanism responsive to thedifferentia action of the two wires will readily suggest themselves topersons skilled in the art.

What I claim is: I

1. The combination of a motor subject to variations from itspredetermined speed, a pair of vibrating elements having differentnatural vibratory periods, means for vibrating said elements at afrequency corresponding with the speed of the motor, and meansresponsive to the differential action of said vibrating elements andtending to hold said motor at substantially its predetermined speed.

2. The combination of an electric motor subject to variations from apredetermined speed, a pair of vibrating elements having differentnatural vibratory periods, means responsive to the predetermined speedof vsaid motor for vibrating said elements at a frequency intermediatetheir respective natural frequencies, and means responsive to thedifferential action of said vibrating elements for varying theexcitation of said motor.

3. The combination of an electric motor subject to variations from apredetermined speed, a pair of stretched Wires differently tuned, meansresponsive to the predetermined speed of the motor for vibrating saidwires at a frequency intermediate their natural frequencies, and meansresponsive to differences in amplitude of said vibrating wires forvarying the excitation of said motor. v

4. The combination of a pair of vibrating elements tuned respectively tohigh and low frequency, means for normally vibrating said elements at anintermediate frequency and control mechanism responsive to thedifference in vibratory amplitude of said elements.

5. The combination of a motor subject to variations from a normal speed,a pair of stretched wires having different normal vibratory frequencies,electromagnetic means responsive to the predetermined speed of saidmotor for vibrating said wires at an intermediate frequency, a swingingelement responsive to the difference in amplitude of vibration of saidwires, and means controlled by said swinging element for var ing theexcitation of said motor to hold 1t at substantially normal speed.

6. Apparatus of the character described comprising in combination, adevice subject to variations from a predetermined speed, a plurality ofvibrating elements having different natural vibratory periods, meansresponsive to the predetermined speed of said device for vibrating saidelements at a frequency intermediate their respective naturalrequencies, and means responsive to the diiferential action of saidvibrating elements for maintaining substantially the predetermined speedof said device.

7. Apparatus of the character described comprising, in combination, adevice subject to variations in speed, a plurality of vibrating elementshaving different natural vibratory periods, means for vibrating saidelements at a frequency dependent upon the.

speed of said device, and means responsive to the differential action ofsaid vibrating elements for maintaining substantially a predeterminedspeed of saiddevice.

8. Apparatus of .the character described comprising, in combination, anelectric motor subject to variations in speed, a lurality of vibratingelements having di erent natural vibratory periods, means for vibratingsaid elements at a frequency dependent upon the speed of said motor, andmeans responsive to the differential action of said vibrating elementsfor varying the excitation of said motor.

9. Regulating apparatus for a device subject to variations in speedcomprising, in combination, a plurality of vibrating elements eachhaving a natural vibration frequenc means under the control of saiddevice or causing variations in the relative amplitudes of saidvibrating elements dependent upon variations in speed of said dev1ce,andmeans dependent upon the variations in relative amplitudes of saidelements for controlling the speed of said device.

10. Apparatus of the character described comprising, in combination, arotating ar'-. mature subject to variations in speed, an exciting fieldfor said armature, a plurality of vibrating elements each having anatural frequency of vibration, means under the control of said armaturefor causing variations in the relative amplitudes of said vibratingelements dependent upon variations in s eed of said armature, and meansdepen ent upon the variations in relative amplitudes of said elementsfor controlling the excitation of saidfield.

11. Apparatus of-the character described comprisin in combination, arotating armature su ject to variations in speed, an

of the armature for vibrating said elements at a'frequency intermediatetheir respective natural frequencies, and means responsive to thedifferential action of said vibrating elements for varying theexcitation of said field.

13. Apparatus of the character described comprising, in combination, adevice subject to variations in speed, a plurality of v1-'brating'elements each having a natural frequency of vibration, meansfor vibrating said elements at a frequency corresponding with the speedof said device, and means responsive to the differential action of saidvibrating elements for maintaining substantially constant the speed ofsaid device.

14:. Regulating apparatus of the character described comprising, incombination, a device subject to variations from a predetermined speed,a pair of vibrating elements each having a natural frequency of vibra--tion, means responsive to the predetermined speed of said device forvibrating said elements at a frequency intermediate their respeotivenatural frequencies, and means responsive to the differential action ofsaid vibrating elements for maintaining substantially the predeterminedspeed of sald device.

In testimon whereof I aflix my signature, in presence 0 two witnesses.

JOHN B. TAYLOR. Witnesses:

Lomsn Barns, M. A. BILL.

